For centuries efforts have been made to achieve enhanced coloration of skin for a myriad of reasons. Historically, a variety of implements have been used to indelibly color the skin, ranging from sharply pointed bones, teeth, thorns, guitar strings, safety pins, wood, plastic or any metallic object sufficient to penetrate the skin with color so as to leave a visible mark. These colorful or black and white marks, also known as tattoos, have been applied for adornment, symbolic, patriotic, ethnic or religious identification and artistic expression on a human canvas of skin. Interest also exists in the area of cosmetic, corrective or camouflage tattooing (medical micropigmentation) as a method to provide, for example, permanent makeup, or restore color and/or symmetry to the eyebrows, lips, eyelids, breasts, scars and skin conditions from losses suffered by aging, birth defects (cleft lip), cancer treatment (alopecia) or skin changes (hypopigmentation-vitiligo).
Tools to implement a desired intradermal, coloration of the skin with a penetration implement have also evolved over the years. These include early hand tools such as bamboo sticks with strapped needles (a technique still common today in parts of Asia) and motor driven intradermal injection devices. These devices are relied on to inject ink, dye or other marking material (referred to hereafter collectively as “ink” for brevity) just under the skin, so that the ink is retained within the skin and the color of the ink injection pattern is visible. The motorized devices normally comprise a skin-penetrating needle which has the capacity to retain some quantity of ink, a mechanism to reciprocate the needle for repeated punctures of the skin to implant the ink under the skin in the desired pattern, and a housing for the device which the operator holds and often uses to guide the device. There is also typically an off-on switch and power source for the reciprocating drive mechanism. With some devices the operator repeatedly dips the needle into an ink pool to coat the needle, while other devices have built-in reservoirs for the ink from which the ink is fed continuously to the needle.
A number of different devices, particularly with different types of reciprocating needle drives, have been disclosed over the years. Typical of such devices are those described in U.S. Pat. No. 2,840,076 (Robbins: 1976); U.S. Pat. No. 4,508,106 (Angres: 1985); U.S. Pat. No. 4,644,952 (Patips et al.: 1987); U.S. Pat. No. 4,798,582 (Sarath et al.: 1989); and U.S. Pat. No. 5,279,552 (Magnet: 1984).
Examples of pen like (non-motorized) skin marking devices can be seen in U.S. Pat. No. 4,655,912 (Burton: 1987) and U.S. Pat. No. 5,810,862 (Pilamanis: 1998).
Intradermal pigment injection instruments or implements include the use of singular needles. Multi-tip array needles are also featured in the above noted Angres, Pilmanis, and Sarath patents as well as in U.S. Pat. No. 6,030,404 (Lawson et al.: 2000). Reference is also made to the technical report “The Manufacture of Needle Specifically For Tattooing”© Eikon Device Inc., October 1995 with June 1996 revisions, which report is incorporated herein by reference. The needles are designed for penetrating the skin to deliver the ink with the depth being based on insertion depth which, in turn, is dependent upon a variety of factors including the taper and/or diameter of the penetrating needle, the resistance level of the material being penetrated (e.g., the toughness of the skin) as well as environmental factors such as the dryness of the needle and/or skin being penetrated and whether there is wetting or lubrication material on the needle or on the skin being penetrated (or other body material). The invention can also be used for other medical, non-skin use such as medical pigment application to non-skin areas like the cornea of an eye, although the preferred usage and many of the parameters set forth herein are directed at skin penetration.
The age of the person can have an influence on the resistance level to penetration as aging skin tends to lose in collagen level and turgor so as to become more resistant to needle penetration and is also more susceptible to tissue damage from tattoo needles. One's skin also typically becomes thinner than in one's youth, thus playing a role relative to ink penetration levels.
“Single point” needles are typically relatively larger needles that are designed and used alone relative to the holder for line generation (e.g., single line or areas following extensive multiple line repetition). In view of their size, these single point needles typically are more traumatic on the skin leading to greater puffing etc., which can make ink application more difficult and less error free (e.g., if puffing and distortion initiates while the ink application is ongoing in the same area). Single point needles do allow, however, for high definition location application particularly in difficult to reach areas or when attempting to set initial external boundary regions.
Multiple needle configurations such as that described in Lawson are used to penetrate the skin over large areas. They are, however, not always well suited for areas such as those described above where a certain skin topography, desired ink configuration and/or a body arrangement makes the particular array arrangement of the multi-array needles ill suited for a desired use. This entails having to switch out multiple needle types to accommodate the application requirement or the use of a plurality of different holder/needle set combinations.
Furthermore, microscopic examination of tattooed skin to determine the depth and location of ink or colorant means (e.g., particles (pigments)) reveals pigment lying as deep as 2.6 mm in some applications. This depth may be acceptable on some parts of the body, but is excessive on others (e.g., consider the thickness of eyelid skin at 0.5-0.75 mm). Placing colorants too deeply results in skin changes and scarring as well as impaired visibility of the pigment. Considering that, unlike many body tattoos, in excess of 90% of cosmetic tattoos are placed on the face (e.g., eyeliner application) where they are constantly visible without the benefit of a covering (clothes), there exists a particularly high level of concern with respect to the final look and quality of the cosmetic tattoo application. That is, there is little room for visible errors when dealing with cosmetic surgery on the face such as the lips, eyelids, brow, etc. Also, from the foregoing, it is also apparent the putting colorants into the skin is quite variable from a variety of perspectives. This variation is particularly prevalent when dealing with cosmetic surgery on the face where the topography changes and skin texture changes can be more dramatic even in small areas of application. Because of this, there often exists in the prior art techniques a requirement to repeat an application (e.g., eyeliner application repeats) due to poor or improper penetration and/or the providing of insufficient pigment. This is especially undesirable and inefficient in that the initial procedure (which requires a healing process as well) is at least in part a wasted effort.